Cophixalus australis, Hoskin, Conrad J., 2012

Hoskin, Conrad J., 2012, Two new frog species (Microhylidae: Cophixalus) from the Australian Wet Tropics region, and redescription of Cophixalus ornatus, Zootaxa 3271, pp. 1-16 : 4-8

Cophixalus australis sp. nov.

Southern Ornate Nursery-frog ( Figs 2 A, 2B)

Material examined. Holotype: QMJ43655, male, Mt Spec, Paluma Ra. (18°57′S, 146°11′E), north-east Queensland, C. Corben, 11 January 1976. Paratypes: QMJ39923, North Bell Peak, Malbon Thompson Ra. (17°05′S, 145°53′E); QMJ50700, Douglas Ck Rd, Kirrama Ra. (18°12′S, 145°45′E, elevation 800 m); QMJ61251, Mid Macks, Kirrama Ra. (18°02′30″S, 145°36′30″E); QMJ65377, Kirrama Ra. (18°01′30″S, 145°35′30″E, elevation approx. 900 m); QMJ70701, Lacey Ck, Mission Beach (17°51′0 5″S, 146°04′50″E, elevation 40 m); QMJ70710, QMJ70711, Loop track at picnic ground, Paluma township (19°00′30″S, 146°12′30″E, elevation 900 m); QMJ70782, The Crater/Mt Hypipamee National Park (17°25′54″S, 145°29′0 8″E, elevation 980 m). Additional material: An additional 296 individuals were measured in the field, and mating calls were measured from 141 of these ( Table 2 ).

Diagnosis. Cophixalus australis sp. nov. can be identified from similar congeners, except C. ornatus and C. hinchinbrookensis sp. nov., by the presence of large, truncated finger pads and by call, which is a ‘beep’ rather than a call with obvious pulses or notes. Cophixalus australis sp. nov. can be reliably identified from C. ornatus and C. hinchinbrookensis sp. nov. genetically, using the loci outlined in Hoskin et al. (2011). For 16S mtDNA, diagnostic SNPs are presented in Table 3 . It can also be readily identified based on distribution. Cophixalus australis sp. nov. does not co-occur with C. hinchinbrookensis sp. nov. and only narrowly abuts the range of C. ornatus ( Fig. 1 ). Cophixalus australis sp. nov. differs from C. ornatus and C. hinchinbrookensis sp. nov. in multivariate analyses of mating call and some aspects of morphology (Hoskin et al. 2011), but these three species cannot be distinguished on any known single trait. Regarding colour pattern, the groin and posterior thigh generally lack a yellow wash in C. australis sp. nov. (vs. typically present in C. ornatus ; Fig. 2 F).

Etymology. From the Latin australis for ‘southern’, in reference to the fact that this species occurs in the southern half of the Wet Tropics region. The epithet is to be treated as a noun in apposition.

Description of holotype ( Fig. 2 A). QMJ43655; male. Measurements (mm): SVL 22.2; TL 8.2; FL 5.5; HW 7.7; HL 5.4; ED 2.2; EN 1.6; IN 1.3; 3FL 3.1; 3DW 1.1; 4TL 4.6; 4DW 1.0. Head: Narrower than body, triangular in dorsal view; snout moderately truncated at the nares, projecting in profile; canthus rostralis rounded, loreal region steep; nares much closer to tip of snout than to eye, nares anterolateral on tip of snout; eyes large; eye diameter greater than eye to naris distance; internarial distance about equal to distance from eye to naris; tympanum small (less than half diameter of eye) and indistinct beneath overlying skin, bordered dorsally by supratympanic fold. Body: Rotund. Limbs: Hindlimbs short, forearms relatively long; fingers and toes unwebbed; relative finger length 3>2>4>1; fingers 2, 3 and 4 long and slender with large and truncated discs, first finger short with barely expanded small round disc; low, rounded inner and outer palmar tubercles; subarticular tubercles low, moderately prominent; relative length of toes 4>3>5>2>1, toe 4 very long and slender; large, truncated discs on toes 2, 3 and 4, discs smaller and more rounded on toes 1 and 5; low, rounded inner and outer metatarsal tubercles; subarticular tubercles low and rounded; discs on longest fingers larger than discs on longest toes. Skin: Ventral surface generally smooth, finely granular on belly; dorsal surfaces smooth with just a few low tubercles; distinct supra-tympanic fold. Colour pattern in preservative: Dorsal surfaces uneven brown, darker towards the head, with dark smudging on the lateral surface above the axilla and a dark band on the wrist of each forearm; pale lumbar ocelli bordered posteriorly by a dark bar; dark cloacal region. Loreal region dark, and a dark line along tympanic fold. Tympanum pale brown. White patches at the base of the finger and toe discs. Dark brown dorsal colouration merges to lighter brown on flanks. Ventral surface of head and body creamy-brown with fine light brown stippling, particularly under throat. Ventral surfaces of limbs brown; discs brown, tubercles white.

Description of type series (N = 9). Data presented as range followed by mean in brackets. Adult measurements (mm): SVL 18.3–24.3 (21.0); TL 7.4–9.8 (8.7); FL 4.3–5.8 (5.1); HW 6.5–8.0 (7.3); HL 4.9–5.9 (5.3); ED 1.6–2.2 (2.0); EN 1.3–1.7 (1.5); IN 1.2–1.5 (1.3); 3FL 2.8–3.7 (3.2); 3DW 0.9–1.4 (1.2); 4TL 3.9–5.4 (4.6); 4DW 0.7–1.0 (0.8). Adult proportions: TL/SVL 0.37–0.45 (0.42); FL/SVL 0.22–0.27 (0.24); FL/TL 0.53–0.67 (0.59); HW/SVL 0.29–0.39 (0.35); HL/SVL 0.23–0.29 (0.25); HW/HL 1.20–1.53 (1.38); ED/SVL 0.08–0.11 (0.10); EN/HL 0.25–0.33 (0.29); EN/IN 1.01–1.34 (1.16); EN/ED 0.62–0.94 (0.77); 3FL/SVL 0.13–0.18 (0.15); 3DW/SVL 0.045–0.069 (0.056); 4TL/SVL 0.19–0.24 (0.22); 4DW/SVL 0.031–0.045 (0.040); 3DW/4DW 1.13–1.63 (1.39). Comparison of sexes: Based on field measurements ( Table 2 ), females are generally larger (e.g. average SVL 25.5 vs. 22.7), have proportionally larger finger discs, and are bulkier (i.e. heavier relative to SVL). Colour pattern in preservative: Generally as for holotype (N = 5) – light brown background with areas of darker brown smudging and mottling. Several individuals (N = 3) have pale body with broad creamy yellow vertebral band edged with dark brown band. Consistent features on all specimens are: grey/brown triangle on snout, grey on eyelids, dark W-shaped mark on shoulders; pale lumbar ocelli marked behind by dark patch, irregular dark blotch above axilla on lateral surfaces, sometimes with associated dark blotches along the flanks, dark band from snout through eye and along supratympanic fold; generally a dark band on wrist, pale dots at base of finger and toe pads, often dark mottling on hindlimbs. Ventral surfaces variable: evenly pale (N = 6) or mottled grey (N = 2) or brown with white spotting (N = 1). Undersides of limbs generally brown, tubercles and pads generally pale.

Measurements of live individuals. Table 2 presents measurements for 288 males and 8 females in the field.

Colour pattern in life. Dorsal pattern highly variable. There are three broad morphs: (1) ‘mottled’— irregular dark markings on an uneven pale, orange or brown background; consistent dark markings being a dark W-shaped mark in the scapular region, an irregular dark bar across the top of the head between the eyes and a dark mark associated with pale lumbar ocelli, (2) ‘broad band’—a broad cream or yellow vertebral band bordered with black on a brown or dark background, and (3) ‘vertebral line’—a very thin cream or yellow vertebral line on an uneven brown or dark background, usually with accompanying thin line along hindlimbs. The first morph (mottled) is the most common but individuals with vertebral bands are present in most populations. Dorsal markings found on all morphs include pale or yellow lumbar ocelli and a paler triangle on the snout. Dorsal surfaces of limbs mottled with grey, brown or black. Forelimbs usually irregularly marked with orange or yellow, with similar colouration sometimes also present on ankles often similarily tinged. Dorsal colouration merges to white, cream or grey on flanks. Consistent lateral markings include an irregular dark line from nare through eye and along supra-tympanic fold, and a dark irregular bar above the axilla. Groin and posterior thigh similar pale or grey colouration to flanks and with grey mottling. Ventral surfaces usually evenly white, cream, grey or light brown, but sometimes flecked or mottled with darker markings. Iris heavily flecked with gold and pupil often bordered with a red or copper line. No sexual dimorphism in colour pattern evident.

Call. A finely pulsed ‘beep’ ( Fig. 3A ) of the characteristics outlined in Table 2 .

Comparison. Only likely to be confused with other rainforest microhylids. Cophixalus australis sp. nov. can be distinguished from these species (except C. ornatus and C. hinchinbrookensis sp. nov.) by the presence of large, truncated finger pads and by the mating call, which is a finely-pulsed ‘beep’ rather than a call with obvious pulses or notes. Cophixalus australis sp. nov. is phenotypically similar to C. ornatus and C. hinchinbrookensis sp. nov.. There are multivariate differences in mating call and morphology between these three species (Hoskin et al. 2011) but they cannot be identified based on any single known phenotypic trait in the field ( Table 2 ). Colouration and pattern are highly variable within each of these three species. The only difference detected so far is that C. ornatus typically has a yellow wash to the groin and posterior thigh ( Fig. 2 F), which is generally absent in the other two species. The three species can be reliably identified by genetics, representing divergent monophyletic lineages for both mtDNA and nDNA loci (Hoskin et al. 2011). For 16S mtDNA, the SNPs presented in Table 3 and the GenBank sequences listed below can be used for identification. The three species can be identified in the field based on locality, except at sites within the narrow contact zone between C. australis sp. nov. and C. ornatus in the central Wet Tropics ( Fig. 1 ; Table 1).

Genetics. Cophixalus australis sp. nov. is the ‘Central’ lineage referred to in Hoskin et al. (2011). A representative 16S mtDNA sequence for this species from near the type locality is JF743720 (GenBank accession number). Other 16S sequences for C. australis sp. nov. are: JF743692 , JF743693 , JF743695 -97, JF7436999, JF743706 , JF743710 , JF743714 -18, JF743722 , JF743726 , JF743728 , JF743729 , JF743731 -34, JF743738 , JF743740 , JF743744 , JF743745 , JF743747 -49, JF743751 , JF743753 , JF743754 , JF743757 , JF743761 (Hoskin et al. 2011). Cophixalus australis sp. nov. consists of three genetic subgroups: (1) the ‘Mt Bartle Frere’ subgroup (BF), found on the Bellenden Ker Range, south-eastern Atherton Tablelands and Malbon Thompson Range, (2) the ‘Southern’ subgroup (S), found from the southern Atherton Tablelands down to the Paluma Range; and (3) the ‘Lowland’ subgroup (L), found in the lowlands around south-eastern Mt Bartle Frere, the Palmerston Valley area, Tully Gorge and Mission Beach (Hoskin et al. 2011; Fig. 1 ). The taxonomic status of these subgroups is covered in the Discussion.

Distribution. Found in the central and southern Wet Tropics: Malbon Thompson Ra, Mt Bellenden Ker, summit of Mt Bartle Frere and eastern and southern slopes, southern Atherton Tablelands, lowlands of the Innisfail/Mission Beach/Tully Gorge area, Kirrama Ra and Paluma Ra (south to Mt Halifax) ( Fig. 1 ; Table 1; Hoskin et al. 2011). The northern extent of the distribution on the Atherton Tablelands is approximately a line between Herberton and Topaz, with C. australis sp. nov. known to occur at sites at least as far north as Mt Hypipamee, Millaa Millaa Falls, Topaz and Lamins Hill ( Fig 1 ; Table 1; Hoskin et al. 2011). Cophixalus australis sp. nov. is common throughout mid and high elevations (up to 1500 m) but lowland populations (<400 m a.s.l.) are localised and only known from scattered sites in the central Wet Tropics: south-eastern slope of Mt Bartle Frere, Palmerston, Tully Gorge, Mission Beach and Innisfail area.

Habitat and habits. Cophixalus australis sp. nov. inhabits rainforest. It also occurs in montane heath and boulder fields where these occur among rainforest, and in some areas it occurs in wet sclerophyll forest adjacent to rainforest. Males call during and following wet weather. Males call from elevated postions (0.3–3 m above the ground) such as on stems and trunks, among foliage and dead vegetation caught amongst foliage, palm axils, tree hollows and among rocks. The most common calling position is facing head upwards on a vertical stem approximately 0.5–1.5 m off the ground. Females are rarely encountered at night. When a female approaches a calling male, he changes his call to a courtship call (a shorter, higher pitched call) and leads the female to a nest chamber in the earth, under a rock, or in a hollow in a rotten log or stem ( Zweifel 1985; Hoskin 2004; Felton et al. 2006). Similar behaviour has been observed in Cophixalus kulakula ( Hoskin & Aland 2011). Mate choice in C. australis sp. nov. is believed to involve multiple steps: male call, male leading and nest quality ( Felton et al. 2006). As for other Australian microhylids ( Zweifel 1985; Hoskin 2004), C. australis sp. nov. is a terrestrial breeder, with small clutches of large eggs. A clutch of 15 unpigmented eggs has been found under leaf litter in a tree hole, and was attended by a male (Hoskin 2004). Cophixalus australis sp. nov. is an abundant frog throughout its range.

Site Locality Dec. Lat/Long Species

1 Mt Lewis, Carbine Tableland -16.5108, 145.2695 C. ornatus 2 Harris Peak, Macalister Range -16.6728, 145.4527 C. ornatus 3 Kuranda -16.8267, 145.6544 C. ornatus 4 Lamb Range -17.1063, 145.5913 C. ornatus 5 Mt Baldy -17.2769, 145.4472 C. ornatus 6 Lake Eacham -17.2827, 145.6314 C. ornatus 7 Gillies Hwy, top of the range -17.2158, 145.6738 C. ornatus 8 Red Cedar, Gadgarra Forest Reserve -17.2725, 145.6666 C. ornatus 9 Butchers Creek area -17.3383, 145.7109 C. ornatus 10 Gourka Rd (end) -17.3794, 145.7628 C. ornatus 11 Mt Bartle Frere, W access, 700 m -17.3761, 145.7719 C. ornatus 12 Mt Bartle Frere, W access, 900 m -17.3770, 145.7829 C. ornatus 13 Mt Bartle Frere, W access, 1100 m -17.3820, 145.7881 C. ornatus , C. australis 14 Mt Bartle Frere, W access, 1350 m -17.3838, 145.7957 C. australis 15 Mt Bartle Frere, E access, 1350 m -17.4081, 145.8186 C. australis 16 Mt Bartle Frere, E access, 1100 m -17.4158, 145.8238 C. australis 17 Mt Bartle Frere, E access, 900 m -17.4155, 145.8272 C. australis 18 Mt Bartle Frere, E access, 700 m -17.4171, 145.8329 C. australis 19 Mt Bartle Frere, E access, 500 m -17.4212, 145.8381 C. australis 20 Mt Bartle Frere, E access, 300 m -17.4203, 145.8438 C. australis 21 Mt Bartle Frere, E access, 100 m -17.4378, 145.8590 C. australis 22 Mt Bellenden Ker -17.2677, 145.8691 C. australis 23 Malbon Thompson Range -17.0863, 145.8796 C. australis 24 Lamins Hill -17.3560, 145.7242 C. australis 25 Gourka Rd (halfway) -17.3759, 145.7290 C. australis 26 Old Boonjie Rd (start), Topaz area -17.3837, 145.7115 C. australis 27 Mausdale, Topaz area -17.3967, 145.7022 C. australis

continued next page C. ornatus C. australis sp. nov. C. hinchinbrookensis sp. nov.

Figures

FIGURE 1. Phylogeny (A) and distributions (B) of C. australis sp. nov., C. hinchinbrookensis sp. nov. and C. ornatus. (A) Maximum likelihood tree constructed from 513 bp 16 S mtDNA. The phylogeny shows the relationship between C. ornatus, C. australis sp. nov. and C. hinchinbrookensis sp. nov. The tree also shows the three subgroups within C. australis sp. nov.: Mt Bartle Frere region (BF), Lowland (L) and Southern (S). Numbers at major nodes are Bayesian posterior probabilities. (B) Map of the Wet Tropics region of north-east Australia and an enlargement of the Atherton Tablelands-Mt Bartle Frere region. The coloured dots show the most common mtDNA lineage at each site, with dot colour matching the phylogeny. The site numbers match the locality details in Table 1. This figure is modified from Figs 3 and C 1 in Hoskin et al. (2011).

FIGURE 2. Photos of: (A) the holotype of C. australis sp. nov. (QMJ 43655); (B) C. australis sp. nov. in life, Mt Hypipamee (photo: Conrad Hoskin); (C) the holotype of C. hinchinbrookensis sp. nov. (QMJ 44166); (D) C. hinchinbrookensis sp. nov. in life, Hinchinbrook Island (photo: Alex Anderson); (E) the holotype of C. ornatus (R 222); (F) C. ornatus in life, Kuranda (photo: Conrad Hoskin).

FIGURE 3. A single representative call of: (A) C. australis sp. nov., Tully Falls, 750 m a. s. l., 18 ° C; (B) C. hinchinbrookensis sp. nov., Mt Diamantina, Hinchinbrook Island, 770 m a. s. l., 19 ° C; (C) Cophixalus ornatus, Butchers Ck, 715 m a. s. l., 18.5 ° C. These calls were selected because they are from similar altitudes and temperatures, and because they fall near the group centroid of variation within each species from analyses in Hoskin et al. (2011). Waveforms display amplitude (y - axis) against time (x - axis, seconds); Spectrograms display call frequency (y - axis) and intensity (degree of shading) against time (x - axis, seconds).